In order to effectively run monetization across the publisher properties we require partners to incorporate a number of ads.txt entries.

The file is hosted by the publisher (example here) and lists the supply and demand partners allowed to access publishers inventory with monetization purposes. Insticator & OKO provides access to more than 40 demand and supply partners to provide best fill rate and prices for each and every ad opportunity.

To make sure our publishers are set for success, we have an automatic crawler scanning ads.txt directory and providing visibility which ads.txt entries are missing. The data can be accessed via the dashboard 24/7 and is updated every 24 hours.

Root domains vs Subdomains

All the buyers are able to read the file at the root level and will not recognize other variations. If you’re a publisher who has a series of subdomains, you want to list out those subdomains in the root domain ads.txt file to be sure that the networks are seeing them as well.


If any site has a subdomain or a number of those, like in the example above, we need to ensure that ads.txt is always added to the root domain, like Even if only subdomain is being monetize.

Best practices: some DSPs might be checking subdomains for ads.txt (e.g., so we always recommend to set redirect from subdomain ads.txt page to the root domain ads.txt page to ensure the consistency of entries is held across all subdomains. If its impossible, we would need to ensure every subdomain has the same set of ads.txt entries. Having 404 error for subdomain ads.txt might cause revenue loss in the long term perspective.

If you have any questions regarding ads.txt entries, please reach out to [email protected] - we'd be happy to help!